the·ba·ine (thē'bə-ēn', thĭ-bā'ĭn) n. A poisonous alkaloid, C19H21NO3, obtained from opium. Also called paramorphine.
[New Latin (herba) thēbaia, (herb of) Thebes, Egyptian opium (from Latin Thēbaea, feminine of Thēbaeus, Theban, from Thēbae, Thebes, from Greek Thēbai) + -ine2.]